Add winrm functionality to null provisioner (#2525)

* Add new functions to communicator helper to return the user, password, host, based on the communicator used.

This implementation can help then generalize the provisioeners later on.

* Update null builder checks to utilize the new functions and check for ANY hostname or user or password

* Update builder to user any hostname

builder/null/builder.go

@@ -30,7 +30,7 @@ func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packe
 	steps := []multistep.Step{
 		&communicator.StepConnect{
 			Config: &b.config.CommConfig,
-			Host:   CommHost(b.config.CommConfig.SSHHost),
+			Host:   CommHost(b.config.CommConfig.Host()),
 			SSHConfig: SSHConfig(
 				b.config.CommConfig.SSHUsername,
 				b.config.CommConfig.SSHPassword,

builder/null/config.go

@@ -31,19 +31,19 @@ func NewConfig(raws ...interface{}) (*Config, []string, error) {
 	if es := c.CommConfig.Prepare(nil); len(es) > 0 {
 		errs = packer.MultiErrorAppend(errs, es...)
 	}
-	if c.CommConfig.SSHHost == "" {
+	if c.CommConfig.Host() == "" {
 		errs = packer.MultiErrorAppend(errs,
-			fmt.Errorf("ssh_host must be specified"))
+			fmt.Errorf("a Host must be specified, please reference your communicator documentation"))
 	}
 
-	if c.CommConfig.SSHUsername == "" {
+	if c.CommConfig.User() == "" {
 		errs = packer.MultiErrorAppend(errs,
-			fmt.Errorf("ssh_username must be specified"))
+			fmt.Errorf("a Username must be specified, please reference your communicator documentation"))
 	}
 
-	if c.CommConfig.SSHPassword == "" && c.CommConfig.SSHPrivateKey == "" {
+	if c.CommConfig.Password() == "" && c.CommConfig.SSHPrivateKey == "" {
 		errs = packer.MultiErrorAppend(errs,
-			fmt.Errorf("one of ssh_password and ssh_private_key_file must be specified"))
+			fmt.Errorf("one authentication method must be specified, please reference your communicator documentation"))
 	}
 
 	if c.CommConfig.SSHPassword != "" && c.CommConfig.SSHPrivateKey != "" {

helper/communicator/config.go

@@ -55,6 +55,42 @@ func (c *Config) Port() int {
 	}
 }
 
+// Host returns the port that will be used for access based on config.
+func (c *Config) Host() string {
+	switch c.Type {
+	case "ssh":
+		return c.SSHHost
+	case "winrm":
+		return c.WinRMHost
+	default:
+		return ""
+	}
+}
+
+// User returns the port that will be used for access based on config.
+func (c *Config) User() string {
+	switch c.Type {
+	case "ssh":
+		return c.SSHUsername
+	case "winrm":
+		return c.WinRMUser
+	default:
+		return ""
+	}
+}
+
+// Password returns the port that will be used for access based on config.
+func (c *Config) Password() string {
+	switch c.Type {
+	case "ssh":
+		return c.SSHPassword
+	case "winrm":
+		return c.WinRMPassword
+	default:
+		return ""
+	}
+}
+
 func (c *Config) Prepare(ctx *interpolate.Context) []error {
 	if c.Type == "" {
 		c.Type = "ssh"